RESUMEN
High temperature and sulfur concentrations in geothermal sulfur fumaroles host unique microbial ecosystems with niche-specific metabolic diversity and physiological functions. In this study, the microbial communities and their functionalities associated with the Dayoukeng geothermal field and the rock-soil-plant continuum were investigated to underpin the microbial modulation at different distances from the fumaroles source. At the phylum level, Bacteroidota, Planctomycetota, Armatimonadota, and Patescibacteria were abundant in plant samples; Elusimicrobiota and Desulfobacterota were in the rock samples while Nitrospirota, Micrarchaeota, and Deinococcota were dominant in the soil samples. Acidophilic thermophiles were enriched in samples within close proximity to the fumaroles, primarily at a distance of 1 m. The sulfur and iron-oxidizing acidophilic bacterial genera such as Acidothiobacillus and Sulfobacillus were abundant in the rock samples. The thermoacidophilic archaeon Acidianus and acidophilic bacteria Acidiphilium were abundant in the soil samples. Additionally, Thermosporothrix and Acidothermus were found abundant in the plant samples. The results of the functional annotation indicated that dark sulfur oxidation, iron oxidation, and hydrogen oxidation pathways were abundant in the soil samples up to 1 m from the fumaroles, while methanogenic and fermentation pathways were more prevalent in the soil samples located 10 m from the fumaroles. Interestingly, the results of this study indicated a higher microbial richness and abundance of acidophilic communities in the soils and plants compared to the rocks of the DYK fumarolic geothermal field.
Asunto(s)
Microbiota , Suelo , Bacterias/metabolismo , Hierro/metabolismo , Azufre/metabolismo , ARN Ribosómico 16S/metabolismo , Microbiología del SueloRESUMEN
KEY MESSAGE: OsHsp18.0 plays a key role in cross-protection of rice seedlings from damages to photochemical systems and cellular membranes, caused by Cd and Cu stresses.
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Metales Pesados , Oryza , Oryza/genética , Metales Pesados/toxicidad , Plantones/genética , Cadmio/toxicidadRESUMEN
Mud volcanoes are the most dynamic and unstable sedimentary structures in the areas of tectonic compression like the subduction zones. In this study, we comprehensively analyzed the distribution of minerals as well as diversity, abundance and metabolic potential of the microbial communities of major mud volcanic groups across Taiwan namely Chu-kou Fault (CKF), Gu-ting-keng Anticline (GTKA), Chi-shan Fault (CSF), and Longitudinal Valley Fault (LVF). The mud volcano fluids recorded relatively higher Na and Cl contents than the other elements, particularly in the CKF and GTKA groups. The highest microbial diversity and richness were observed in the CSF group, followed by the GTKA group, whereas the lowest microbial diversity was observed in the CKF and LVF groups. Proteobacteria were common in all the sampling sites, except WST-7 and WST-H (Wu-Shan-Ting) of the CSF group, which were abundant in Chloroflexi. The halophilic genus Alterococcus was abundant in the Na-and Cl-rich CL-A sites of the CKF group. Sulfurovum was dominant in the CLHS (Chung-Lun hot spring) site of the CKF group and was positively correlated with sulfur/thiosulfate respiration, which might have resulted in a higher expression of these pathways in the respective group. Aerobic methane-oxidizing microbial communities, such as Methylobacter, Methylomicrobium, Methylomonas, and Methylosoma, constituted a dominant part of the LVF and CSF groups, except for the YNH-A and YNH-B (Yang-Nyu-Hu) sites. The WST-7 and JS sites were abundant in both methane-producing and methane-oxidizing microbial communities. The LGH-F1 (Lei-Gong-Huo) site was dominated by both methanotrophic and methylotrophic genera, such as Methylomicrobium and Methylophaga, respectively. Methylotrophy, methanotrophs, and hydrocarbon-degrading pathways were more abundant in the LVF and CSF groups but not in the remaining groups. The results of this study extend our knowledge of the diversity, abundance, and metabolic functions of prokaryotes in major terrestrial mud volcanoes in Taiwan.
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Sedimentos Geológicos , Microbiota , Sedimentos Geológicos/química , ARN Ribosómico 16S , Bacterias , Tolnaftato , Taiwán , Filogenia , Metano/análisis , Minerales/metabolismoRESUMEN
Heavy metal release from harsh ultramafic settings influences microbial diversity and function in soil ecology. This study aimed to determine how serpentine mineralosphere bacterial assemblies and their functions differed in two different plate-tectonic plains and mining exposure sites under heavy metal release conditions. The results showed that the Proteobacteria, Actinobacteria, Cyanobacteria, Planctomycetes, and Chloroflexi were the most abundant bacterial groups among all the sites. The log10-based LDA scores highlighted that some specific groups of bacterial assemblies were enriched in plate-tectonic plains and mining activity areas of the serpentine mineralosphere. Functional prediction revealed that the abundance of heavy metal (Cr and Ni) resistance and biogeochemical cycles involving functional KEGG orthology varied in samples from plate-tectonic plains and mining activity sites. The bipartite plot showed that the enrichment of the biogeochemical cycle and heavy metal resistance functional genes correlated with the abundance of serpentine mineralosphere bacterial groups at a 0.005% confidence level. The co-occurrence network plot revealed that the interconnection pattern of the indigenous bacterial assemblies changed in different plate-tectonic plains and mining exposure areas. Finally, this study concluded that due to heavy metal release, the variation in bacterial assemblies, their functioning, and intercommunity co-occurrence patterns were clarified the synergetic effect of mineral-microbial geochemical weathering process in serpentine mining areas.
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Metales Pesados , Microbiota , Contaminantes del Suelo , Bacterias/genética , Metales Pesados/análisis , Minerales , Suelo , Microbiología del Suelo , Contaminantes del Suelo/análisisRESUMEN
The current study deals with the analysis of sound absorption characteristics of foxtail millet husk powder. Noise is one the most persistent pollutants which has to be dealt seriously. Foxtail millet is a small seeded cereal cultivated across the world and its husk is less explored for its utilization in polymer composites. The husk is the outer protective covering of the seed, rich in silica and lingo-cellulose content making it suitable for sound insulation. The acoustic characterization is done for treated foxtail millet husk powder and polypropylene composite panels. The physical parameters like fiber mass content, density, and thickness of the composite panel were varied and their influence over sound absorption was mapped. The influence of porosity, airflow resistance, and tortuosity was also studied. The experimental result shows that 30-mm thick foxtail millet husk powder composite panel with 40% fiber mass content, 320 kg/m3 density showed promising sound absorption for sound frequency range above 1000 Hz. We achieved noise reduction coefficient (NRC) value of 0.54. In view to improve the performance of the panel in low-frequency range, we studied the efficiency of incorporating air gap and rigid backing material to the designed panel. We used foxtail millet husk powder panel of density 850 kg/m3 as rigid backing material with varying air gap thickness. Thus the composite of 320 kg/m3 density, 30-mm thick when provided with 35-mm air gap and backing material improved the composite's performance in sound frequency range 250 Hz to 1000 Hz. The overall sound absorption performance was improved and the NRC value and average sound absorption coefficient (SAC) were increased to 0.7 and 0.63 respectively comparable with the commercial acoustic panels made out of the synthetic fibers. We have calculated the sound absorption coefficient values using Delany and Bezlay model (D&B model) and Johnson-Champoux-Allard model (JCA model) and compared them with the measured sound absorption values.
RESUMEN
The applicability of C-H functionalization to medicinally important 2-pyridyl-based N-heterocycles suffers from severe challenges owing to the high Lewis basicity of the N-atom. This arrests catalytic activity and yields undesirable positional selectivity due to preferential chelate formation. In this regard, we report a novel palladium(ii)-catalyzed arylation strategy on multiple-N-containing pyridazines by over-riding the functionalization due to a chelated palladacycle. We report a regioselective mono-arylation at the 8-position of diphenyl azolopyridazines without any ortho-C-H activation on the proximal phenyl groups. This methodology presents a broad arylation scope with uncompromised yield and positional selectivity, including the heteroarylation of N-heterocycles, which is an unprecedented feat for these types of molecules.
RESUMEN
Measuring tissue oxygenation in vivo is of interest in fundamental biological as well as medical applications. One minimally invasive approach to assess the oxygen partial pressure in tissue (pO2) is to measure the oxygen-dependent luminescence lifetime of molecular probes. The relation between tissue pO2 and the probes' luminescence lifetime is governed by the Stern-Volmer equation. Unfortunately, virtually all oxygen-sensitive probes based on this principle induce some degree of phototoxicity. For that reason, we studied the oxygen sensitivity and phototoxicity of dichlorotris(1, 10-phenanthroline)-ruthenium(II) hydrate [Ru(Phen)] using a dedicated optical fiberbased, time-resolved spectrometer in the chicken embryo chorioallantoic membrane. We demonstrated that, after intravenous injection, Ru(Phen)'s luminescence lifetime presents an easily detectable pO2 dependence at a low drug dose (1 mg∕kg) and low fluence (120 mJ∕cm2 at 470 nm). The phototoxic threshold was found to be at 10 J∕cm2 with the same wavelength and drug dose, i.e., about two orders of magnitude larger than the fluence necessary to perform a pO2 measurement. Finally, an illustrative application of this pO2 measurement approach in a hypoxic tumor environment is presented.
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Colorantes Fluorescentes/química , Imagen Óptica/métodos , Oxígeno/análisis , Fenantrolinas/química , Rutenio/química , Animales , Línea Celular Tumoral , Embrión de Pollo , Membrana Corioalantoides/irrigación sanguínea , Membrana Corioalantoides/química , Membrana Corioalantoides/efectos de los fármacos , Membrana Corioalantoides/metabolismo , Colorantes Fluorescentes/farmacocinética , Colorantes Fluorescentes/toxicidad , Humanos , Neoplasias Experimentales , Fibras Ópticas , Imagen Óptica/instrumentación , Compuestos Organometálicos/química , Compuestos Organometálicos/farmacocinética , Compuestos Organometálicos/toxicidad , Presión Parcial , Fenantrolinas/farmacocinética , Fenantrolinas/toxicidad , Rutenio/farmacocinética , Rutenio/toxicidad , Distribución TisularRESUMEN
Cervical cancer, the second most common malignancy among women, is mainly caused by human papilloma virus (HPV) infection. In HPV-positive cervical cancer cells, the activity of p53 and the induction of p21 are inhibited by the HPV oncoproteins E6 and E7. Therefore, blocking the activity of E6 and E7 would serve as an important therapeutic target in these cancer cells. In this study, anisomelic acid (AA), a natural compound belonging to the same diterpenoid family of bioactive compounds as taxol, was found to deplete the E6 and E7 proteins in HPV-positive cervical cancer cells. Consequently, p53 and the p53-responsive gene, p21, were dramatically induced, leading to G2/M-phase cell cycle arrest. AA-mediated cell cycle arrest and p21 expression were canceled when p53 was down-regulated by p53-shRNA. AA also induced p53-independent intrinsic apoptosis by depletion of the cellular inhibitor of apoptosis protein 2 (cIAP2) whose proteosomal degradation is inhibited by E6. The in ovo chick embryo chorioallantoic membrane (CAM) assay showed that anisomelic acid inhibited the tumor growth of the cervical cancer SiHa cells. AA is revealed to hold a novel action modality based on specific targeting of the HPV oncoproteins, which restores p53-mediated growth arrest and induces apoptosis by terminating E6-mediated cIAP2 stabilization.
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Diterpenos/farmacología , Diterpenos/uso terapéutico , Papillomavirus Humano 6/metabolismo , Proteínas E7 de Papillomavirus/antagonistas & inhibidores , Neoplasias del Cuello Uterino/virología , Animales , Embrión de Pollo , Relación Dosis-Respuesta a Droga , Femenino , Células HeLa , Papillomavirus Humano 6/efectos de los fármacos , Humanos , Células MCF-7 , Proteínas E7 de Papillomavirus/metabolismo , Neoplasias del Cuello Uterino/tratamiento farmacológicoRESUMEN
Tissular oxygen concentration plays a key role during photodynamic therapy (PDT). Therefore, monitoring its local oxygen partial pressure (pO2) may help predict and/or control the outcome of a PDT treatment. The first real-time, in vivo measurements of the pO2 in the chicken egg's chorioallantoic membrane, using the delayed fluorescence of photoactivable porphyrins (PAPs), including protoporphyrin IX (PpIX), as monitored with a dedicated optical, fiber-based, time-resolved spectrometer, are reported here. The formation of PAPs/PpIX, photosensitizers of extensive clinical use, was induced in the chicken egg's chorioallantoic membrane (CAM) with aminolevulinic acid. An excellent correlation between the vascular damage induced by PDT and the reduction in tissular pO2 is found. This study suggests that clinical measurement of the pO2 using the PAPs'/PpIX's delayed fluorescence (DF) may be used to individualize in real time the PDT light dose applied.
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Oxígeno/metabolismo , Fotoquimioterapia , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/metabolismo , Protoporfirinas/química , Protoporfirinas/metabolismo , Administración Tópica , Ácido Aminolevulínico/administración & dosificación , Animales , Embrión de Pollo , Membrana Corioalantoides/irrigación sanguínea , Membrana Corioalantoides/efectos de los fármacos , Membrana Corioalantoides/metabolismo , Fluorescencia , Cinética , Fenómenos Ópticos , Distribución TisularRESUMEN
The cancer chemotherapeutic potential of surfactant-cobalt(III) complexes, cis-[Co(bpy)(2)(C(14)H(29)NH(2))Cl](ClO(4))(2)·3 H(2)O (1) and cis-[Co(phen)(2)(C(14)H(29)NH(2))Cl](ClO(4))(2)·3 H(2)O (2) (bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline) on MCF-7 breast cancer cell was determined adopting MTT assay and specific staining techniques. The complexes affected the viability of the cells significantly and the cells succumbed to apoptosis as seen in the changes in the nuclear morphology and cytoplasmic features. Since the complex 2 appeared to be more potent, further assays were carried out on the complex 2. Single-cell electrophoresis indicated DNA damage. The translocation of phosphatidyl serine and loss of mitochondrial potential was revealed by annexin V-Cy3 staining and JC-1 staining respectively. Western blot analysis revealed up-regulation of pro-apoptotic p53 and down-regulation of anti-apoptotic Bcl-2 protein. Taken together, the surfactant-cobalt(III) complex 2 would be a potential candidate for further investigation for application as a chemotherapeutic for cancers in general and estrogen receptor-positive breast cancer in particular.
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Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Cobalto/química , Tensoactivos/química , 2,2'-Dipiridil/química , 2,2'-Dipiridil/farmacología , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Western Blotting , Neoplasias de la Mama/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ensayo Cometa , Daño del ADN/efectos de los fármacos , Femenino , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Fenantrolinas/química , Fenantrolinas/farmacología , Coloración y EtiquetadoRESUMEN
Some water-soluble polymer-copper(II) complexes, [Cu(phen)(l-phe)(BPEI)]ClO(4).4H(2)O (phen=1,10-phenanthroline, l-phe=l-phenylalanine, and BPEI=branched polyethyleneimine), with various amounts of copper(II) chelates in the polymer chain, were prepared by ligand substitution method in water-ethanol medium and characterized by infra-red, UV-visible, EPR spectral and elemental analysis methods. Binding of these complexes with calf thymus DNA (CT DNA) has been investigated by absorption spectroscopy, emission spectroscopy and gel electrophoresis techniques. The experimental results indicate that the amount of copper(II) chelate content in the polymer backbone have marked effect on the binding affinity to CT DNA. Interactions like electrostatic interaction, van der Waals interaction, hydrogen bonding and/or partial intercalation binding modes exist in this system. A sample of polymer-copper(II) complex was tested for its antibacterial and antifungal activity against certain human pathogenic organisms and it was found to have good antibacterial and antifungal activities.
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Antiinfecciosos/química , Cobre , ADN/metabolismo , Polímeros/química , Animales , Antibacterianos/química , Antibacterianos/farmacología , Antifúngicos/química , Antifúngicos/farmacología , Humanos , Ligandos , Fenantrolinas , Fenilalanina , Solubilidad , Análisis EspectralRESUMEN
Some novel water-soluble polymer-copper(II)-phenanthroline complex samples, [Cu(phen)2(BPEI)]Cl(2).4H2O (phen=1,10-phenanthroline, BPEI=branched polyethyleneimine), with different degrees of copper complex content in the polymer chain have been prepared by ligand substitution method in water-ethanol medium and characterized by infrared, UV-visible, EPR spectral and elemental analysis methods. The binding of these complex samples with DNA has been investigated by electronic absorption spectroscopy, emission spectroscopy and gel retardation assay. Electrostatic interactions between DNA molecule and polymer-copper(II) complex molecule containing many high positive charges have been observed. Besides these ionic interactions, van der Waals interactions, hydrogen bonding and other partial intercalation binding modes may also exist in this system. The polymer-copper(II) complex with higher degree of copper complex content was screened for its antimicrobial activity and antitumor activity.